1 Haken: Herr Doktor Jones. We meet again.1 Monty: Colonel Haken!2 Prof. Jones: But... you died in the Grail chamber!2 Haken: Nazi science sneers at the boundary between life and death!3 Monty: But... but... that's interfering with things best left alone by mortals!4 Haken: I'm sorry... Who used the Holy Grail to bring his father back from certain death?

I don't know what the heck they're standing in front of... some sort of greenhouse apparently.
2012-04-20 Rerun commentary: It's the first mention of Nazi science in the comic! This is an historic occasion!

Or at least it was the first time this strip ran, back in 2003. How many of you realised that day was historical when it happened?

In hindsight, my original annotation (above) seems full of portent, does it not?

Oh, and I guess they could be standing inside a building, and the windows are revealing the exterior.